I hear 茶馆 singing, the varied songs I hear

Those of geometers, each one singing his as he measures the length of a line after pulling off a point

The columnist singing his or hers as they sit in their chair and type on their laptop 

The philosopher singing his as he draws horse after horse or Venn diagrams on his paper...

 

几何原本现在学了点和线的定义，我感到好像我已经懂了一半，不少，哈